(1) Make sure that students have good quality nylon rope for the activity given. Nylon rope shows better wave on string.
While doing the activity ask them to observe the position of the coloured mark.
(2) Ask students to observe the motion of the paper boat with the propagation of the ripples on the water.

Note: In the activity 2, while shooting the video we taken care of the other disturbances which could affect it e.g. wind, our movement of foot nearby the bucket, and any high amplitude sound source.